Alloy



Patented Apr. 29, 1924.

ALEQYJ Flo Drawing. (mginal applioationflled may 28, 1919, Serial No. 299,364. Divided filed February 19, 1920. Serial No. 359,803.

To all whom it may concern:

Be it known that we, HENRY C. KIRK and GEORGE H. DUMLER, citizens of the United States of America, the former residing at- Roland Park,Baltimore County, Maryland, and the latter in the city of Baltimore, State of Maryland, have invented certain new and useful Improvements in Alloys, of which the following is a s ecification.

The present app ication is a division of our application No. 299,364, filed May 23,.

1919, which is in part a continuation of our applications 255,040, filed September 21, 1918, and 260,159, filed October 29, 1918.

The invention relates to an alloy of copper, nickel and iron substantially in the roportion of 10% iron, 20% nickel and the alance, approximately 70%, copper. The al- .loys which we have produced in accordance with the disclosure of the foregoing applications comprise a series, having aconsiderable range and the object of the present ap-- plication is to cover the alloys of approximately the proportions above pointed out, and variations of this alloy having similar proportions and substantially the same prop erties.

An alloy which we have made, and which we consider to be included within this definition, contains 18% nickel and 10% iron, the balancebeing copper. It is a white material resembling silver in appearance, ver tenacious, of high tensile strength and wit high ductility. It can be rolled, readily spun and drawn into tubes, also it can be stamped into any'desired sha es.

A metal having the composition of 22 nickel, 11%% iron and the balance copper shows in the Brinell test for hardness #121 and #126. It has a specific gravity of 865 and a weight per cubic inch of 0.31 pounds. It can be rolled from a thickness of .500 to I .009 inch without annealing. Hard rolled,

it has a tensile strength of pounds per square inch, elastic limit 94,500 to 107,000 pounds per square inch, elongation in two inches hard rolled two to four per cent, annealed it has a tensile strength of r3340 to 86,100 pounds, elastic limit 47,000

to 51,000 per square inch, elongation 30 to 26%. As-a sand casting, it has a tensile and this application strength of 10,000 pounds per square inch, and an elastic limit of 30,000 pounds per square inch. Y

This metal is of a white color resembling silver in appearance. It is non-corrosive, most organic acids have no effect on it, and it is remarkably well adapted as a substitute for silver or for any purpose where strength, durability and appearance are important. Comparing it to German silver, it'is much whiter, stronger and not as easily oxidizable.

An alloy containing 20% nickel, 8%% iron, the balance being copper, which is a good alloy for sheet material, wire and so forth, as a sand casting, without annealing, shows an elastic limit of37,730 pounds per square inch, tensile strength of 40,500 ounds per square inch, and an elongation of 4% in two inches. 'The same material cold-rolled shows an elastic limit of 107,000 pounds per square inch, a. tensile strength. of 113,400 pounds per square inch, and an elon ation of 3% in two inches. Annealed it s ows an elastic limit of 39,000 pounds per square inch, a tensile strength of 73,340 pounds per square inch and an elongation of 30% in two inches.

In each instance we have referred to the percentage of nickel and iron. It is understood that the balance of 100 per cent is copper.

In the production of this alloy, to the preferred develo ment of the industry, the nickel has serve as a carrier for introducing the iron into the copper. Investigations show that 2% of nickel will carry 10% to 15% iron into the alloy; that is, 2% of nickel is suflicient to make it possible to form an alloy of copper, nickel and iron, 2% nickel, 10% iron and the balance copper.

according However, the carrying power of nickel, i. e.,

simplest method of making the alloy out of v common commercial material is by dissolv- 20% nickel, 10% iron and ing iron in a molten mixture of nickel and co copper, preferably at the melting point of the mixture, which is closely related to the melting point of nickel, the nickel having a solvent eflect on the iron, which alone has a higher melting point than nickel, and cannot be directl combined with copper.

What we 0 aim and desire to secure by Letters Patent is:

1. An alloy containing copper, nickel and iron in approximately the proportion of the balance ppen.

2. An alloy of copper, nickel and iron, 15

Maryland,

substantially as described.

Signed by us at Baltimore,

this 18th day of February, 1920.

HENRY C. KIRK. GEORGE H. DUMLER.

Witnesses ZELLA KUHN, SELMA STERN. 

